单项选择题
A.It’s quite normal. B.It’s too high. C.It’s cheap indeed. D.It could be cheaper.
A.Hurry to the conference. B.Skip the conference. C.Take the subway. D.Take a bus.
A.They are less likely to run away. B.It’s easier for their masters to train them. C.They are less likely to be shy with human beings. D.It’s easier for them to form a relationship with their masters.